Accrued Expenses (Components Of Accrued Expenses) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Accrued Expenses [Abstract]
Payroll and payroll related	$ 1,112	$ 617
Preclinical and clinical trials	21,453	19,190
Other	1,449	1,592
Total	$ 24,014	$ 21,399